Redirect console messages to /dev/console..

After this change, they will now all go to /tmp/console.log.`date +%m%y%d`

edit file /etc/rc.local

add this line

swcons /tmp/consolelog.`date +%m%d%y`

This will redirect all console messages to this file note it will create a new file new file every time the system is rebooted. 

So you should do clean up of old files once a month or when ever you reboot..